Sierra Metals Inc. has filed a technical report prepared in accordance with National Instrument 43-101 ("NI 43-101") on the Yauricocha Mine (the "Report"). The Report supports the disclosure made by the Company in its news release dated June 27, 2018, entitled "Sierra Metals Announces Positive Preliminary Economic Assessment Results for a 66% Output Expansion at its Yauricocha Mine in Peru to 5,500 Tonnes Per Day Yielding a 486% Return on Investment." The Report is based on technical inputs from various independent consulting groups, including; SRK, Redco, Ingenieria Carillo, Anddes, Tierra Group and Geoservice Engineers and was compiled under National Instrument 43-101 standards by Mining Plus Peru SAC. There are no material differences in the Preliminary Economic Assessment results contained in the Report from those disclosed in the June 27, 2018 news release. This subsequent report is based on the results from a 43-101 Technical Report on the Yauricocha Mine dated November 10, 2017 with an effective date of July 31, 2017 entitled "NI 43-101 Technical Report on Resources and Reserves Yauricocha Mine Yauyos Province, Peru", that was prepared by independent SRK Consulting (U.S.) Inc. The Report included PEA results with: After-tax Net Present Value (NPV): US$393 Million at an 8% discount rate, Return on Investment (ROI): 486%, After-tax Payback Period Life of Mine Capital: 4.1 years, Life of Mine Capital Cost: USD 238 Million Net After-tax Cash Flow: USD 532 million, Total Operating Unit Cost: USD 43.86/tonne, Mine Processing Rate: 5,500 tonnes per day (TPD), Plant Processing Rate: 5,500 TPD, Life of Mine: 10 years based on existing Mineral Resource Estimate and Life of Mine Zinc Payable Production 621.1 million Pounds.